Question

in the equation ax+by=20 and bx+ay=16, the value for x=2 and y=1. What are the coefficient a and b?

Answer 1

if you substitute the values then the equations become
2a+b=20
and
2b+a=16

Answer 2

So try solving it or I can help you solve it

Answer 3

yeah I know you get those but what next

Answer 4

okay so multiply the first equation by 2
you get
4a+ 2b = 40

Answer 5

the 2nd equation is 2b+a = 16
so now subtract this equation from 4a+2b = 40

Answer 6

you will get
(4a+2b)-(a+2b) = 40-16

Answer 7

From this you will get the value of a

Answer 8

Using the value of a you will get the value of b

Answer 9

well 40- 16= 24 so then you know that a=24 would you substitute 24 for a in the next equation?

Answer 10

Nope see on the left hand side of the equation, it is 3a not a

Answer 11

So 3a = 24

Answer 12

ok...so then how would it look? don't solve the equation but just so I can see how it will be set up

Answer 13

i will set it up in a drawing and attach it

Answer 14

ok

Answer 15

so then it would look like 2(24)+b=20